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**soroban****Member**- Registered: 2007-03-09
- Posts: 452

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. . (Or name it after your favorite ethnic group.)

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**DrSteve****Member**- Registered: 2010-11-15
- Posts: 10

Very interesting. I believe that you should include the original numbers you're multiplying by in the table (in this example they are crossed out because 76 is even).

Without giving away the details to others that want to prove this, the solution involves powers of 2.

**Challenge problem:**This technique can be generalized by using powers of n for any other fixed positive integer n>2. How would the algorithm change in this case? (Hint: you need one additional column).

If you're going to be taking the SAT, check out my book:

http://thesatmathprep.com/SAT_Sales_Page.html

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**barbie19022002****Member**- Registered: 2013-05-24
- Posts: 1,314

For your kind information I searched this one in net it is actually Egyptian Multiplication.............

Jake is Alice's father, Jake is the ________ of Alice's father?

Why is T called island letter?

think, think, think and don't get up with a solution...

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,315

Hi;

I am afraid that it is mostly referred to in books as Russian peasant multiplication.

**In mathematics, you don't understand things. You just get used to them.**

**I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.**

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**barbie19022002****Member**- Registered: 2013-05-24
- Posts: 1,314

Its very silly, why will the Russian peasants use multiplication..........

Jake is Alice's father, Jake is the ________ of Alice's father?

Why is T called island letter?

think, think, think and don't get up with a solution...

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,315

If they did not multiply, they would be extinct.

**In mathematics, you don't understand things. You just get used to them.**

**I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.**

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**barbie19022002****Member**- Registered: 2013-05-24
- Posts: 1,314

Extinct? but peasants are still there in the world.... especially in India....

Jake is Alice's father, Jake is the ________ of Alice's father?

Why is T called island letter?

think, think, think and don't get up with a solution...

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,315

That is true so they are multiplying.

**In mathematics, you don't understand things. You just get used to them.**

**I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.**

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**barbie19022002****Member**- Registered: 2013-05-24
- Posts: 1,314

But, why only multiplication...why not addition... though it is a long process..

Why is T called island letter?

think, think, think and don't get up with a solution...

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,315

Hmmm, multiplying as in increasing the population.

**In mathematics, you don't understand things. You just get used to them.**

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**barbie19022002****Member**- Registered: 2013-05-24
- Posts: 1,314

but, if the population increases then all the natural resources will be over...

Why is T called island letter?

think, think, think and don't get up with a solution...

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,315

That is true. But it is another question entirely.

**In mathematics, you don't understand things. You just get used to them.**

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**barbie19022002****Member**- Registered: 2013-05-24
- Posts: 1,314

Ya, but in any how it is getting connected to it..

Why is T called island letter?

think, think, think and don't get up with a solution...

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,315

The comment was a play on words. Multiplying has two meanings.

**In mathematics, you don't understand things. You just get used to them.**

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**barbie19022002****Member**- Registered: 2013-05-24
- Posts: 1,314

Ya, I did understand that...

Why is T called island letter?

think, think, think and don't get up with a solution...

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,315

Anyway, soroban is correct. If you can multiply and divide by 2 you can do RPM.

**In mathematics, you don't understand things. You just get used to them.**

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**barbie19022002****Member**- Registered: 2013-05-24
- Posts: 1,314

RPM- you mean russian peasant multiplication??

Why is T called island letter?

think, think, think and don't get up with a solution...

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,315

It sure is. We already know those peasants know how to multiply.

**In mathematics, you don't understand things. You just get used to them.**

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